Black swallowers, Chiasmodon niger, are characterized by their three canine teeth on either jaw. The second and third canines are depressible, with the third canine pointed toward the inside of its mouth.

The black swallower’s unique jaws and massive stomach allow it to swallow meals that are much larger than its own body. The fish is seen here with a full belly, but as Compton writes, it's only temporary: "[He] spit up undigested jawbones, cheekbones and backbones... [and] he surveyed the world with hunger again."